To slow down a moving vehicle, for example a passenger car or commercial vehicle, so-called wheel brakes are customarily used. However, when used for a longer period of time, for example when driving down a mountain, wheel brakes of this type may become thermally overloaded, which may result in reduced braking action or a failure of the wheel braking system. The provision of a sustained-action braking device, which enables a longer-lasting braking action, is therefore known, in particular in the case of vehicles having a great total weight.
For example, a so-called engine braking system, whose braking power is achieved from a drag of an internal combustion engine and a braking power generated by throttling an exhaust gas flow in a discharge system, is known as a sustained-action braking device. An elevated braking power is achievable using so-called decompression engine brakes or so-called exhaust valve braking systems.
In certain conventional exhaust valve braking systems, the exhaust valve brake is usually activated or deactivated by the vehicle driver, using a switch. A method for selecting multiple predefined braking powers of the exhaust valve brake, using a step switch, is also conventional.
The exhaust valve brake is activatable only when the accelerator pedal is not in operation. The functionality of the accelerator pedal is deactivated via a selection logic when the exhaust valve brake is activated via the switch.
Certain conventional exhaust valve braking systems have the disadvantage that they are not easy to operate. Certain conventional exhaust valve braking systems also have the disadvantage that they do not provide the braking power to be achieved to be accurately specified.